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1.
Abstract. The five‐membered heteroelement cluster THF · Cl2In(OtBu)3Sn reacts with the sodium stannate [Na(OtBu)3Sn]2 to produce either the new oxo‐centered alkoxo cluster ClInO[Sn(OtBu)2]3 ( 1 ) (in low yield) or the heteroleptic alkoxo cluster Sn(OtBu)3InCl3Na[Sn(OtBu)2]2 ( 2 ). X‐ray diffraction analyses reveal that in compound 1 the polycyclic entity is made of three tin atoms which together with a central oxygen atom form a trigonal, almost planar triangle, perpendicular to which a further indium atom is connected through the oxygen atom. The metal atoms thus are arranged in a Sn3In pyramid, the edges of which are all saturated by bridging tert‐butoxy groups. The indium atom has a further chloride ligand. Compound 2 has two trigonal bipyramids as building blocks which are fused together at a six coordinate indium atom. One of the bipyramids is of the type SnO3In with tert‐butyl groups on the oxygen atoms, while the other has the composition InCl3Na with chlorine atoms connecting the two metals. The sodium atom in 2 has further contacts to two plus one alkoxide groups which are part of a[Sn(OtBu)2]2 dimer disposing of a Sn2O2 central cycle. The hetero element cluster in 2 thus combines three closed entities and its skeleton SnO3InCl3NaO2Sn2O2 consists of three different metallic and two different non‐metallic elements.  相似文献   

2.
The title compounds, [Sn(C6H5)2(C5H4S5)] and [Sn(C5H4S5)2], respectively, are of interest because they can be regarded as intermediate in nature between chelates and heterocyclic compounds containing the C3S5 fragment. In contrast with the essentially normal bond lengths and angles within the mol­ecules, the molecular conformations are somewhat unexpected, as are the intermolecular contacts found in the case of the latter compound.  相似文献   

3.
The title compound, C12H12O2N2·H2O, is described. Although the keto–enol form of the ligand in solution is known, the compound crystallized in the orthorhombic space group P212121 with only the monohydrated 1,3‐diketo form. The intermolecular hydrogen bond between the imino N—H group of the ligand and O atom of the water mol­ecule recorded an H?O distance of 1.73 (3) Å.  相似文献   

4.
The lithium salt (HC–NCMe3)2SiFNLiR ( 1 ) R = C6H3(2,6‐CHMe2)2 reacts with trichlorogallium under displacement of the lithium ion by GaCl3 to give the adduct [(HC–NCMe3)2SiFN] [(GaCl3)R·Li(thf)4]+ ( 1 ). Compound 1 thermally loses LiCl and forms the bicyclic ring intermediates V and VI . Compound  VI adds the aniline H2NC6H3(2,6‐CHMe2)2 and the unsaturated, seven‐membered ring compound –NCMe3–CH2–CH=NCMe3GaCl2–NR–SiFNHR– ( 2 ) is obtained. The addition is accompanied by an enamine‐imine‐tautomerism and proves the Lewis acid character of the silicon atom in an unknown 3‐center‐2‐electron interaction of one nitrogen atom with the silicon and gallium atoms. Quantum chemical calculations of the thermal isomerisation process and crystal structures of 1 and 2 are reported.  相似文献   

5.
2,2‐Difluor‐1,3‐diaza‐2‐sila‐cyclopentene – Synthesis and Reactions N,N′‐Di‐tert‐butyl‐1,4‐diaza‐1,3‐butadiene reacts with elemental lithium under reduction to give a dilithium salt, which forms with fluorosilanes the diazasilacyclopentenes 1 – 4 ; (HCNCMe3)2SiFR, R = F ( 1 ), Me ( 2 ), Me3C ( 3 ), N(CMe3)SiMe3 ( 4 ). As by‐product in the synthesis of 1 , the tert‐butyl‐amino‐methylene‐tert‐butyliminomethine substituted compound 5 was isolated, R = N(CMe3)‐CH2‐CH = NCMe3. 5 is formed in the reaction of 1 with the monolithium salt of the 1,4‐diaza‐1,3‐butadiene in an enamine‐imine‐tautomerism. 1 reacts with lithium amides to give (HCNCMe3)2SiFNHR, 6 – 12 , R = H ( 6 ), Me ( 7 ), Me2CH ( 8 ), Me3C ( 9 ), H5C6 ( 10 ), 2,6‐Me2C6H3 ( 11 ), 2,6‐(Me2CH)2C6H3 ( 12 ). The reaction of 12 with LiNH‐2.6‐(Me2CH)2C6H3 leads to the formation of (HCNCMe3)2Si(NHR)2, ( 13 ). In the presence of n‐BuLi, 12 forms a lithium salt which looses LiF in boiling toluene. Lithiated 12 adds this LiF and generates a spirocyclic tetramer with a central eight‐membered LiF‐ring ( 14 ), [(HCNCMe3)2Si(FLiFLiNR)]4, R = 2,6‐(Me2CH)2C6H3. ClSiMe3 reacts with lithiated 12 to yield the substitution product (HCNCMe3)2SiFN(SiMe3) R, ( 15 ). The crystal structures of 1 , 5 , 6 , 9 , 11 , 13 , 14 are reported.  相似文献   

6.
The lithium salts of the Me3Si‐ as well as Me3Si‐ and Me2SiF‐substituted Cyclotrisilazanes I and II react with tert‐butylacylchloride under ring contraction and formation of the cyclodisilazane‐silylester, Me3SiN(SiMe2–N)2SiMe2–O–CO–CMe3 ( 1 ). The lithium salt of the fluorodi‐methylsilyl‐substituted cyclotrisilazan III forms with benzoylchloride primarily in the analogous reaction the carboxy‐silyl‐amide, Me2SiF(N–SiMe2)2SiMe2–NH–CO–C6H5+ ( 2 ), which can be converted with III and benzoylchloride into the cyclodisilazane‐silylester, Me2SiF(NSiMe2)2SiMe2–O–CO–C6H5, ( 3 ). A silylester substituted six‐membered disila‐oxadiazine ( 4 ) is the result of the reaction of the lithiated cyclotrisilazane, (Me2SiNH)2, (Me2SiNLi) with tert‐butyl‐acylchloride. The reaction includes anionic ring contraction and can be rationilized by a process analogous to keto‐enol‐tautomerism. Dilithiated octamethyl‐cyclotetrasilazane, (Me2SiNHMe2SiNLi)2, reacts with tert‐butyl‐acylchloride or benzoylchloride in a molar ratio 1:2 to yield symmetrically acylestersubstituted cyclodisilazanes, (RCO–O–SiMe2–NSiMe2)2, R = C6H5 ( 5 ), CMe3 ( 6 ). The reaction mechanisms are discussed and the crystal structures of 2 and 6 are reported.  相似文献   

7.
The title compounds, C8H10O2, (I), and C12H14O2, (II), occurred as by‐products in the controlled synthesis of a series of bis­(gem‐alkynols), prepared as part of an extensive study of synthon formation in simple gem‐alkynol derivatives. The two 4‐(gem‐alkynol)‐1‐ones crystallize in space group P21/c, (I) with Z′ = 1 and (II) with Z′ = 2. Both structures are dominated by O—H?O=C hydrogen bonds, which form simple chains in the cyclo­hexane derivative, (I), and centrosymmetric dimers, of both symmetry‐independent mol­ecules, in the cyclo­hexa‐2,5‐diene, (II). These strong synthons are further stabilized by C[triple‐bond]C—H?O=C, Cmethylene—H?O(H) and Cmethyl—H?O(H) interactions. The direct intermolecular interactions between donors and acceptors in the gem‐alkynol group, which characterize the bis­(gem‐alkynol) analogues of (I) and (II), are not present in the ketone derivatives studied here.  相似文献   

8.
In the title four compounds, C13H11N·C7H4N2O6, (I), C15H15N·C7H4N2O6, (II), C16H17N·C7H4N2O6, (III), and C16H17N·C7H4N2O6, (IV), the donor and acceptor mol­ecules are stacked alternately to form one‐dimensional columns. In (I), the N‐methyl group of the donor is nearly eclipsed with respect to one of the nitro groups of the neighboring acceptor in a column, whereas the N‐iso­propyl, N‐butyl and N‐iso­butyl groups are in anti positions with respect to one of the nitro groups of the neighboring acceptor in compounds (II)–(IV).  相似文献   

9.
The syntheses, X‐ray structural investigations and calculations of the conformational preferences of the carbonyl substituent with respect to the pyran ring have been carried out for the two title compounds, viz. C15H14N2O2, (II), and C20H16N2O2·C2H3N, (III), respectively. In both mol­ecules, the heterocyclic ring adopts a flattened boat conformation. In (II), the carbonyl group and a double bond of the heterocyclic ring are syn, but in (III) they are anti. The carbonyl group forms a short contact with a methyl group H atom in (II). The dihedral angles between the pseudo‐axial phenyl substituent and the flat part of the pyran ring are 92.7 (1) and 93.2 (1)° in (II) and (III), respectively. In the crystal structure of (II), inter­molecular N—H⋯N and N—H⋯O hydrogen bonds link the mol­ecules into a sheet along the (103) plane, while in (III), they link the mol­ecules into ribbons along the a axis.  相似文献   

10.
In the title compound, C13H13N5O4·H2O (4,5′‐cyclo­wyosine·H2O), the cyclization forces a syn arrangement of the aglycon with respect to the sugar moiety. The ribo­furan­ose part of the mol­ecule displays a β‐d configuration with an envelope C1′‐endo pucker. The mol­ecules are arranged in columns along the short a axis and are linked to water mol­ecules through O—H?O and O—H?N hydrogen bonds.  相似文献   

11.
At 160 K, the gluco­pyran­osyl ring of the title compound, C20H28ClIO13, has a near‐ideal 4C1 conformation and the fructo­furan­osyl ring has a twist 4T3 conformation. The two hydroxy groups are involved in intra‐ and intermolecular hydrogen bonds, with the latter interactions linking the mol­ecules into infinite one‐dimensional chains. The absolute configuration of the mol­ecule has been determined.  相似文献   

12.
Comparison of the structures of strychninium N‐phthaloyl‐β‐alaninate N‐phthaloyl‐β‐alanine, C21H23N2O2+·C11H8NO4·C11H9NO4, and brucinium N‐phthaloyl‐β‐alaninate 5.67‐hydrate, C23H27N2O4+·C11H8NO4·5.67H2O, reveals that, unlike strychninium cations, brucinium cations display a tendency to produce stacking inter­actions with cocrystallizing guests.  相似文献   

13.
Yellow–orange tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) dihydrate, [Cd(C8HN4O2)2(H2O)4]·2H2O, (I), and yellow tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) 1,4‐dioxane solvate, [Cd(C8HN4O2)2(H2O)4]·C4H8O2, (II), contain centrosymmetric mononuclear Cd2+ coordination complex molecules in different conformations. Dark‐red poly[[decaaquabis(μ2‐3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κ2N:N′)bis(μ2‐3‐cyano‐4‐dicyanomethylene‐1H‐pyrrole‐2,5‐diolato‐κ2N:N′)tricadmium] hemihydrate], [Cd3(C8HN4O2)2(C8N4O2)2(H2O)10]·0.5H2O, (III), has a polymeric two‐dimensional structure, the building block of which includes two cadmium cations (one of them located on an inversion centre), and both singly and doubly charged anions. The cathodoluminescence spectra of the crystals are different and cover the wavelength range from UV to red, with emission peaks at 377 and 620 nm for (III), and at 583 and 580 nm for (I) and (II), respectively.  相似文献   

14.
The analysis of the title compound, [Mg(H2O)6](C7H8N5O4)2·2H2O, continues our study of the reactivity of metal ions with N‐protected amino acids. The Mg ion lies on an inversion centre with Mg—O 2.0437 (10)‐2.0952 (10) Å. The [Mg(H2O)6]2+cations, anions and water mol­ecules are linked by an extensive hydrogen‐bond network.  相似文献   

15.
The mol­ecule of the title compound, C23H40O4Si2, features an approximate non‐crystallographic C2 symmetry axis. The aldehyde group is disordered over two positions with similar occupancies. The geometry of the isolated mol­ecule was studied by ab initio quantum mechanical calculations employing a mol­ecular orbital Hartree–Fock method. The calculations reproduce well the equilibrium geometry but slightly overestimate the value of the Si—O bond lengths of the trioxadisilepine ring.  相似文献   

16.
The crystal structure of the title complex, {[Cu3(C2H3O2)2(OH)2(H2O)4](C10H6O6S2)}n, is built of infinite polymeric cationic {[Cu3(C2H3O2)2(H2O)4(OH)2]2+}n chains stretching along the a axis, with naphthalene‐1,5‐disulfonate (1,5‐nds) anions in between. One independent CuII cation and the 1,5‐nds anion occupy special positions on crystallographic inversion centres. Each CuII cation has an octa­hedral coordination environment formed by two carboxyl O atoms, two hydroxo O atoms and two water mol­ecules. The carboxyl­ate and hydroxo groups perform a bridging function, linking adjacent Cu atoms in the chain, with a shortest Cu⋯Cu distance of 2.990 (3) Å. The chains are further linked into a three‐dimensional supra­molecular framework via hydrogen‐bonding inter­actions involving the sulfonate groups of the 1,5‐­nds dianions.  相似文献   

17.
The structure of the title compound, C22H24N2O9S2, is described. This compound consists of a sugar ring and a heterocyclic base linked unusually by an S atom. The sugar is in a 4C1 chair conformation and forms dihedral angles of 49.54 (4) and 33.42 (5)° with the thia­diazole and phen­yl rings, respectively. The S atom occupies an equatorial position of the sugar ring and lies 1.807 (2) Å out of the corresponding mean plane.  相似文献   

18.
The two title mononuclear compounds are four‐coordinate bis[N‐(5‐oxo‐4,4‐diphenyl‐4,5‐dihydro‐1H‐imidazolidin‐2‐ylidene)glycinato]copper(II) dimethylformamide disolvate, [Cu(C17H14N3O3)2]·2C3H7NO, (I), and five‐coordinate aquabis[N‐(5‐oxo‐4,4‐diphenyl‐4,5‐dihydro‐1H‐imidazolidin‐2‐ylidene)glycinato]copper(II) dimethylformamide disolvate, [Cu(C17H14N3O3)2(H2O)]·2C3H7NO, (II). In (I), the CuII ion lies on an inversion centre with one‐half of the complex molecule in the asymmetric unit, while in (II) there are two independent ligand molecules in the asymmetric unit, with the CuII ion and coordinated water molecule located on a general position. In both crystal structures, the complex molecules assemble in ribbons via N—H...O hydrogen‐bond networks.  相似文献   

19.
The structure of the title compound, (C5H12N)4[V10O26(CH3O)2], reveals the presence of four protonated piperidin­ium cations and a [{V10O26}(OCH3)2]4− polyanion having an embedded centre of inversion. The compound is distinguished by presenting, in contrast with other anionic deca­vanadates, two meth­oxy groups bridging the outermost V atoms, and it becomes the first example of this type among reported deca­vanadates.  相似文献   

20.
The title compound, C11H12F2N4O3, exhibits an anti glycosylic bond conformation, with a torsion angle χ = −117.8 (2)°. The sugar pucker is N‐type (C4′‐exo, between 3T4 and E4, with P = 45.3° and τm = 41.3°). The conformation around the exocyclic C—C bond is −ap (trans), with a torsion angle γ = −177.46 (15)°. The nucleobases are stacked head‐to‐head. The crystal structure is characterized by a three‐dimensional hydrogen‐bond network involving N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds.  相似文献   

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